Phimosis means that the foreskin of the penis is too tight and so cannot be pulled back off the rounded head of the penis (glans).
In paraphimosis, the foreskin has been pulled back (retracted) but cannot be returned to the original position. Paraphimosis needs emergency medical treatment to prevent complications.
What is phimosis?
Phimosis is normal in babies and infants. Almost all boys have a foreskin at birth that cannot be pulled back. The foreskin usually cannot be pulled back before the age of 2 years.
Attempts to pull back the foreskin at this stage can increase the risk of developing 'abnormal' phimosis in later life.
For most boys the foreskin can usually be pulled back by the age of 10 years of age. Nearly all boys are able to pull back the foreskin by age 16-17 years.
One cause of phimosis is called balanitis xerotica obliterans (BXO). This causes a whitish colour or a thickened, raised area (plaque) on the glans of the penis or the foreskin. It is a fairly common cause of phimosis at puberty.
Phimosis is not a problem unless it causes difficulties, such as obstructing the flow of urine, causing blood in the urine (haematuria) or causing pain.
Abnormal phimosis is usually caused by episodes of infection of the foreskin (called balanoposthitis). The repeated episodes of infection are often caused by poor hygiene. The repeated episodes of infection cause scarring which eventually results in phimosis.
Normal phimosis in babies and young children often causes no symptoms. However, the end of the penis (glans) may balloon when passing urine. Occasionally normal phimosis may cause recurrent urinary tract infections.
Abnormal phimosis may cause painful erections, blood in the urine (haematuria), recurrent urinary tract infections, pain and a weak urine stream. There may be swelling, redness and tenderness of the foreskin. There may also be a discharge from the end of the penis, with some pus.
How common is phimosis?
Phimosis affects about 1 in 12 boys aged 6-7 years and about 1 in 100 aged 16-18 years.
Abnormal phimosis can then occur at any age.
Phimosis usually occurs in uncircumcised boys and men but can occur after circumcision if any remaining excessive skin becomes scarred and thickened.
Female phimosis (clitoral phimosis) can occur but it is uncommon and poorly understood. It may cause pain with sex (dyspareunia).
What tests are needed?
A swab may be taken to confirm whether there is any infection. Otherwise no tests are needed.
For children with normal phimosis, usually no treatment is needed and the phimosis can be expected to resolve with time. You should avoid trying to forcefully pull back the foreskin as this can cause scarring and risks abnormal phimosis developing in later life.
Personal hygiene is very important, including regular but gentle cleaning under the foreskin if it can be pulled back. Always leave the foreskin covering the glans of the penis after cleaning.
Topical steroid creams or gels applied to the preputial ring may be useful.
Phimosis persisting after the age of 2 years may be considered for further treatment, particularly if there is recurrent balanoposthitis or recurrent urinary tract infection. The options are plastic surgery or circumcision.
One plastic surgery alternative to circumcision is called preputioplasty. This involves making a slit in the foreskin so that the foreskin can be pulled back more easily.
What are the complications of phimosis?
Phimosis is a risk factor for cancer of the penis.
What is paraphimosis?
Paraphimosis occurs when the tight foreskin can't be replaced to its natural position because the glans swells. This is a medical emergency. Always check there is nothing around the penis that restricts the blood supply, such as a ring, rubber band or hair.
- There is swelling (oedema) around the constricting band that is usually the prepuce. There may also be pain on erection.
- Infants may just present with being very irritable.
- A carer may discover the condition incidentally in a debilitated patient.
- In later stages, the glans may become a blue or black colour.
The most common cause is not replacing the foreskin over the glans after a urinary catheter is passed into the bladder. Other causes include:
- Scarring of the prepuce after repeated forcible retraction in an attempt to 'cure' a physiological phimosis.
- Vigorous sexual activity.
- Chronic balanoposthitis (especially if you have with diabetes).
- Piercing of the penis - can lead to paraphimosis.
- Gentle compression with a saline-soaked swab followed by pulling the foreskin back over the glans is usually successful.
- If simple methods don't work then emergency treatment in hospital is needed.
- After correction of the paraphimosis, circumcision may be recommended but is not always needed.
Complications of paraphimosis
Failure to correct the paraphimosis will cause inadequate blood flow to the glans of the penis and this may cause gangrene.
Further reading and references
Chan IH, Wong KK; Common urological problems in children: prepuce, phimosis, and buried penis. Hong Kong Med J. 2016 Jun22(3):263-9. doi: 10.12809/hkmj154645. Epub 2016 May 6.
Hayashi Y, Kojima Y, Mizuno K, et al; Prepuce: phimosis, paraphimosis, and circumcision. ScientificWorldJournal. 2011 Feb 311:289-301. doi: 10.1100/tsw.2011.31.
Bragg BN, Leslie SW; Paraphimosis. StatPearls Publishing. Jan 2018.
Douglawi A, Masterson TA; Updates on the epidemiology and risk factors for penile cancer. Transl Androl Urol. 2017 Oct6(5):785-790. doi: 10.21037/tau.2017.05.19.